Crankpin grinding machine



May 19, 1936. A

H.IA. slLvEN CRANKPVIN GRINDING MACHINE 4 sheetssheex 1 .Filed Sept. l29, 1934 9' Hevba'r R. Suva CRW W.

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May 1,9, 1936. H. A. slLvEN 041,215 I cnmxrm aanname Mmmm Filed sept. 29, 1954 4 sheets-sneer:

FEED cYuNoER WHEEL FEED VALVE f N n m www Hevbev R ven W* e@ @ma GMM ' May 19, 1936. H. A. SILVEN I CRANKPIN @BINDING MACHINE 4 Sheets-Sheet 5 `N116@ sept. 29, 1934 May 19 1936. l H. A. siLvl-:N 2,041,215

GRANKPIN GRINDING MACHINE Fild sept. 29, 1934 4 sheets-sheet 4 u 4i-(WM ms W3 m 5 um Wo si ign! W, 2a m x Herbev R. *Sven Patented May 19,' 1936l UNITED STATES' rATl-:NT` orrlvc'l:

cnANxrrN GnINDmG/MACHINE Herbert A. Silven, Worcester, Mass., assignor to Norton Company,` Worcester, Mass., a corporation of Massachusetts Application September 29, 1934, Serial No. 746,158

` 15 claims. (c1. 514:2)

This invention relates to grinding machines, and more particularly to a control mechanism for a. hydraulically driven cylindrical grinding machine.A

Hcretofore, various types of hydraulic drive mechanisms havebeen applied to control the various moving parts of a grinding machine, namely, longitudinal table traverse, transverse movement of theA wheel toward and from the work, and movement of the steadyrest shoe toward and from its operative position in engage- Vment with the Work, In most of the previous constructions, the control of the hydraulically actuated parthas been under individual and separate control requiring the operator to move several control levers in operation of the machine.

In certain types of cylindrical grinding, such as the grinding of a cylindrical crankpin of a crankshaft, it is necessary for the wheel and the steadyrest shoe to be removed from engagement with the Work through a considerable distance to separate the wheel and work rest sufiiciently fromthe Work to allow the longitudinal traversing movement of the work table yto position the next pin opposite the grinding wheel. Heretofore, to accomplish this result, it has been necessary to either manually or hydraulically move the wheel to its rearward position and then by means of separate control to remove the work rest shoe to its inoperative position. Similarly,

when it is desired to grind ,a given pin on a crankshaft, it has been necessary for the operator to advance the steadyrest shoe into operative engagement with the surface of the Work either manually or by the operation of a manvually controlled mechanism before the Wheel vslide control is moved to bring the Wheel into grinding relation with the work piece, but this has necessitated va considerable amount of the operators attention in seeing to it that the Work rest is in engagement with the work before the grinding operation is started and not only removing the grinding Wheel but also removing -the nism for hydraulically moving the work rest and the wheel slide either simultaneously toward or simultaneously avvay from the work piece being 5 ground. A

Itis another object of this invention to provide a hydraulically driven grinding machine with a. single control lever which serves to admit fluid under pressure to simultaneously separate the wheel and Work rest from engagement with the work or to simultaneously move the wheel and rest into operative engagement with the work.

It is still another object ofthis invention to provide a main control valve which serves as a hydraulic interlock to prevent longitudinal movement of the work support when the work rest shoe is in operative engagement with the work. f

In the prior practice in the grinding of crankshafts, it has been necessary to provide adequate splash guards to prevent the coolant fluid from being thrown to the front of the machine onto the floor or onto the various parts of the mechanisms on4 the front of the machine, as well as to prevent the operator from being soaked thereby. SplashV guards have been provided which areA easily andreadily removed from the table, so that the operator may after finish grinding i a crankshaft manuallyremove the guards and then lift the crankshaft from the'machine and place a new crankshaft to be ground therein,l and then manually place the guards in an operative position. In some machines, the guards have been afxed to the table, and it has been necessary for the operator to lift a heavy crankshaft up over the guards to place it in position in the work holders, and similarlyr upon completion of the grinding operation, it has been necessary for the operator to reach up over the guard and lift the shaft out of the machine. Each of these prior practices has required undue exertion on the part of the operator and has tended to impair the emciency of the machine.

It is another object of this invention to provide a movable splash guard, which is arranged so that lt is moved automatically into an operating position at the start of thegrindlng operation and is moved Vto an inoperative position ater the grinding operation has been completed.

It is still another object of this invention to, provide a guard having an upper pivotally mounted portion which may be moved to an inoperative position automatically as the Work rest is Withdrawn to an inoperative position.

It is a further object of this invention to provide a movable splash guard which is preferably ailixed to the work rest and arranged so that it may be automatically moved to an operative or inoperative position in timed relation with the movement of the work rest shoe into or out of engagement with the Work.

It is another object of this invention to provide a grinding wheel, work shoe, and a splash guard which are arranged to be automatically and simultaneously moved either into or away from an operative position.

Other objects will be apparent from the following disclosure.

One embodiment of this invention has been illustrated in the drawings, in which like reference numerals indicate like parts:

Fig. 1 is a front elevation of a hydraulically driven crank-pin grinding machine embodying this invention.

Fig. 2 is a fragmentary diagrammatic perspective view showing the hydraulic system and the control levers and valves;

Fig. 3 is a right-hand end view of the machine, having parts broken away and shown in section to more clearly bring out the constructional details of the machine;

Fig. 4 is a fragmentary elevation, on an enlarged scale, showing the work rest and its operating parts in section;

Fig. 5 is a longitudinal sectional view showingI the details of the work clamping and releasing mechanism; and

Fig. 6 is a cross-sectional View, taken approximately on the line l6 6 of Fig. 4, showing the splash guard. l

This invention consists broadly in providing a double head rotatable work support which is mounted on a longitudinally movable carriage. The carriage Work table is moved longitudinally by a fluid pressure mechanism. A grinding wheel slide is provided for a transverse movement to move the grinding wheel transversely relatively toward or from the work piece bymeans of a fluid pressure piston and cylinder mechanism. A work rest is provided for movement into or out of engagement with the surface of the work piece being ground and is preferably controlled by a fluid pressure piston and cylinder mechanism. A control valve is provided which is in-` terconnected between the wheel slide actuating cylinder and the work rest actuating cylinder so that when the valve is moved to one position, fluid is admitted to cause the grinding wheel and the work rest to separate and move to an inoperative position away from engagement with the work; and when moved to a second position, serves to admit fluid to the feed cylinder land work rest cylinder to simultaneously move the work rest shoe and the grinding wheelinto-operative engagementwith the work piece being ground.

The uid pressure system is provided with a main control valve which is arranged to prevent longitudinal movement ofthe work support when either the grinding wheel or work rest or both of them are in operative engagement with the Work.

A movable splash guard is provided which is preferably to be moved automatically to and from an operating position.r The Wheel feeding mechanism, the work rest shoe actuating mechanism and the splash guard actuating mechanism are preferably interconnected so that the grinding wheel, the shoe and the guard may be moved automatically and simultaneously into or out of operative position before and after thefgrinding operation.

A machine illustrating one embodiment of this invention'has been shown in the drawings, having the base l0 which is arranged to support a transversely movable wheel slide Il mounted on the usual V-way l2 and flat way i3, such as is a well known and common practice in the grinding machine art. The base I0 also supports a work supporting table I5 which ls arranged for a longitudinal movement relative to the base I0 on a V- way I6 and at way Il. The wheel slide Il rotatably supports a grinding wheel 2li which is mounted on one end of a wheel spindle 2|. The grinding wheel may be rotated by any suitable driving mechanism, such as are well known in the grinding art. For simplicity of illustration, a motor driven wheel spindle drive has been illustrated comprising an electric motor 23 mounted on the wheel slide Il. 'I'he motor 23 is provided with a driving pulley 24 which is connected by driving belts 25 with a driven pulley 26 on the outer end of the wheel spindle 2l. The driving belt 25 may be an ordinary flat belt or may comprise a multiple V-type belt drive in which a plurality of V shaped belts ride in a plurality of grooves on the driven pulley.

A suitable work supporting and rotating mechanism is provided comprising a pair of opposed double work supporting and rotating heads which engage and grip opposite ends of a crankshaft t0 be ground. Such a mechanism may be similar, for example, to the construction illustrated in the prior patent to Silven and Belden No. 1,837,342 dated December 22, 1931, to which reference may be had for details of disclosure as to the work head and the work clamping mechanism. In the preferred construction, a pair of opposed work supporting and rotating heads 30 and 3| are mounted on the work supporting table I5 and may be formed integrally therewith or ladjustably mounted thereon. In order that the crankshaft may be rotated uniformly from opposite ends, it is desirable to provide a synchronized work drive for rotating the two opposed work clamping heads. As illustrated in the drawings, a crankshaft 32 may have its opposite ends clamped in opposed rotatable work holders 33 (only one of which has been illustrated) which are rigidly aflixed to face plates 34 mounted on the inner end of each work rotating spindle 35. In order that the work spindles may be synchronously rotated. a driving mechanism is provided including a drive shaft 31 in the base of the machine, which is rotated from any suitable source of powe such as is well known in the art. The positively driven shaft 31 may be connected by means of a clutch 38 to drive a shaft 39, also rotatably mounted in the base. The shaft 39 carries a sprocket B0 which drives through a link chain 4I to a sprocket carries at its outer ends sprockets 45 which drive link :nains -46. The link chains 46 engage 2,041,215 sprockets 41 mounted on the end of each spindle y 35 to rotate the same.

In the preferred construction, the heads 30 and 3| are adjustably mounted on the work table I5 so that they may be adjusted longitudinally relative thereto to accommodate crankshafts of different lengths. To 'permit longitudinal movement of the head, it is desirable to provide aA driving mechanism for the work spindles which is fixed relative to the table.` In the drawings, the casings 48 are provided rigidly supported on the table I5 and are arranged independent of the heads 30 or 3|, so that the heads may be adjusted longitudinally of the table without disturbing the driving mechanism: Detaiisof this construction are illustrated in Fig. 5, which shows the gear l casing 48 as independent of the head 3|.

The driven sprockets 41 are keyed to sleeves 50, only one of which has been illustrated in the is contained within the casings 48 rigidly Vilxed.

to opposite ends of the table I5.

The, work clamping mechanism is provided to clamp the work in the opposed work heads. Details of the clamping device have not been illustrated in the present case, since they do not constitute part of the present invention. For details of construction of the work heads; reference may be had to the prior patent to Silven and Belden No. 1,837,342. The work clamping mechanism in the preferred construction comprises a spring actuated toggle which controls the movement of the clamping jaw to clamp the work rigidly in 4positionV on the machine. As illustrated in Fig.

5, a piston 55 and cylinder 56 for unclamping `the work may be mounted inaxial alignment with the work rotating spindle, if desired, instead of being connected to an offset piston 'and cylinder,

as illustrated in the prior Silven' and Belden patent. The work table may be traversed manually by means of a hand wheel 60 mounted on the outer end of a shaft 6| which also carries the gear 62 meshing with a, gear 63.y 'I'he gear 63 -in turn meshe's with a rack bar 64 mounted on the front of tlework table I5.

The wheel slide II may .befed toward and from the work manually, for eiample, by means of a hand wheel 68,.,mounted`on a shaft 69. The shaft 69 carries a gear 10 meshing with a gear 1I mounted onihe outer end of a shaft 12. The inner end of the shaft 12 is formed as a feed screw 13 meshing with a nut 14 depending from the Wheel slide It will be readily appreciated from thisco'nstruction that manual rota- 'tion of the feed wheel 68 in either direction serves lto cause a movement of the grinding wheel either toward or from' the work, as desired.

In the preferred construction, the grinding wheel slide and the work supporting table may be moved hydraulically by means of a fluid pressure system including an interlocked arrangement between the transversely movable wheel slide and the longitudinally movable work table so that only one of these mechanisms may be moved hydraulically at a given time. For details of disclosure of this mechanism, reference may be had to the prior patent to Belden and Silven No. 1,905,127 dated April 25, 1933. Such' avfluid pressure mechanism may comprise a tank or sump in the base, a fluid pressure pump 9| which is arranged to convey iiuid to a main control valve 92. The main control valve is actuated byfa manually operable lever 93 and is arranged todirect fluid under pressure ,through a pipe 94 to a wheel feed control valve 95 or through pipe 96 to a work table traverse control valve 91. The valve 91 is connected by pipes 98 and 99 with opposite ends of` a cylinder |00 to admit iluid on opposite sides of a piston |0| which is connected by .a piston rod |02 with the table I5. A manually operable lever |03 serves to' actuate valve '91'so as to admit uid to either endV of the cylinder |00 so as to cause the table I5 to move in the desired direction to position the work piece relative to the grinding wheel' 20.

f Fluid passing through the valve 95 is admitted either throughpipe |05 or |06 to cylinder 01 to cylinder chambers on opposite sides of a piston A |08 which is connected by a piston rod |09 to the rear en d of feed screw I3 so as to cause either a forward or reverse feeding movement of the grinding wheel. The valve 95 is preferably ccntrolled by a manually operable lever H0 which is operatively connected to movethe valve 95 so as to admit fluid to cylinder |01 and cause a forward or rearward feeding movement of the grinding wheel 26. 'The fluid pressure system for controlling the transverse movement of the wheel slide and the longitudinalmovement of theY work table |5 are interconnected oninterlocked by means of the main control valve 92 so that `fluid under pressure may be admitted to move either the grinding wheel or the work while excluding it from the other. For'details of disclosure as to the operation of the interlock, reference may be had, to the prior Patent No. 1,905,127.

In a grinding machine of the type used for grinding crankshafts, it is essential that a suitable steadyrest be provided for steadying the crankshaft 32 during the grinding operation. In the preferred construction, a duid pressure actuated work rest is provided comprising a work Vsteadying shoe ||5 mounted on a transversely movable slide I6 which is supported in a steadyrest frame I|1. The steadyrest support is preferably' rigidly iixed to the base in a position so that the shoe ||5 engages the work at a point directly opposite the grinding wheel 20, so that the work table may be indexed longitudinally of the base vI0 to position the work relative to the grinding wheel without disturbing the position of the work rest which is always in a fixed position opposite to the grinding wheel. The steadyrest` shoe "|I5 is preferably moved to and from an operating position by a fluid pressure mechanism comprising a cylinder IIB'and piston |I9. The piston |I9 is connected by a piston rod |20 with a bracket |2I depending from a slide |22 which is supported within the steaclyrest frame I|1. The slide |22 in turn supports the slide ||6 and shoe II5, so that when fluid under pressure is admitted to either end of cylinder '|I8, a transverse movement is transmitted to the work engaging shoe |I5 to move-the same either toward or from the work.

In order that the shoe may be maintained in the desired adjusted position, a manually operable mechanism is provided to adjust the position of the slide IIB relative to the slide 22. Such a vmechanism as illustrated in the drawings may comprisea screw |23 which is fixed at one end to the slide H9 and passes through a threaded nut ||6 and |22. It will be readily appreciated from the foregoing disclosure that the steadyrest may be set up for a grinding operation so that4 fluid under pressure will move the shoe ||5 into engagement with the work and maintain it in engagementwith the work by fluid under pressure, if desired; it being necessary to merely adjust the position of the knob |25 to relatively position slides ||6 and |22., Or, in the preferred manner of operation, the fluid pressure mechanism may be used merely as a positioning mechanism to rapidly move the shoe ||5 into and out of operative engagement with the work. In such a case, the fluid pressure piston I9 on its forward movement moves until the projecting end of the piston rod |20 engages the end of the cylinder 8, and

,the work shoe ||5 is maintained in operative engagement with the crankpin being ground by manually manipulating the knob |25. "m

To attain one of the objects of .this invention, namely, to cause the grinding wheel and the work rest to rapidly approach or separate from engagement with thework before and after grinding, a suitable arrangement of the uid pressure mechanism is provided which enables the grinding wheel and the work rest shoe to be moved simultaneously either toward or from engagement with the work. In order that the steadyrest shoe ||5 may be moved toward and from engagement with the work simultaneously with and in timed relation with the grinding wheel 20, suitable fluid pressure connections are provided including` pipes '|30 and |3| which are connected with pipes |05 and |06 leading from the wheel feed control valve 95. The pipes |05, |06, |30 and |3| are so connected between the wheel feed control valve 95 and cylinders |01 and Il. Admission of fluid to cause a forward feeding movement of the grinding wheel 20 also serves to admit uid to cylinder ||8 so as to cause a forward approaching movement of the work shoe ||5 so that the grinding wheel 20 and the work steadying shoe ||5 may be moved simultaneously into operative engagement with the work. Similarly, when the control lever is moved to change the position of valve 95 so as to cause a rearward movement of the grinding wheel 20 to separate the wheel from the work, fluid is also admitted through pipe |3| to cylinder ||0 to cause the work steadying shoe ||5 to be simultaneously moved away from operative engagement with the work. It will be readily appreciated from the foregoing disclosure that by manipulation of the wheel feed control lever ||0, the grinding wheel 20 and the work steadying shoe I may be moved either simultaneously to-Y ward the work or simultaneously away from the work, thereby eliminating the necessity of an individual control for each element when it is necessary to change the position of the tableV from one pin to the next, to separate the wheel and the steadyrest shoe by a distance sufficient to allow the clearance of the various crank arms as the table is traversed.

To prevent coolant uid from splashing to the front of the machine and wetting the oor and theoperator, a suitable splash guard is provided. In the preferred construction, the steadyrest frame ||1 is mounted xedly on the base i! vand a splash guard |40 is rigidly fastened to the front end of the steadyrest member. The guard |40 is arranged to catch the splash of coolant uid and direct it to the down slope of the table, so that it is conveyed back to the coolant fluid sump at the rear of the machine.

To attain one of the objects of this invention,

a splash guard is provided which is movable automatically to and from an operating position to eliminate the necessity of the operator lifting a heavy crankshaft up over the splash guard or requiring the operator to remove splash guard during each operation. A movable guard may comprise a movable guard member |4| which is hinged to the xed guard |40 by hinges |'42 and |43. Suitable springs |44 and |45 serve to maintain the upper portion of the guard |4| normally in an operating or vertical position.

In order that the guard |4| may be moved into an inoperative position to permit the operator to load and unload the machine without the necessity of lifting a heavy crankshaft or work piece up and over the top of a relatively high splash guard, an automatically actuated mechanism is provided to move the guard |4| to and from an operative position. In order that the splash guard |4| may be moved to an inoperative position, a T-shaped member |46 is mounted on the steadyrest slide H6. When the steadyrest shoe ||5 and slide ||6 are moved rearwardly, that is, toward the right, as viewed in Fig. 4, a narrow, vertical portion |41 of the T-shaped member |46 rides in a slot |48 in the guard |4I, and the horlzontal portions |49 of the T engage the guard |4| and continued movement of the slide ||6 rocks the guard |4| into the position |4Ia, as indicated in Fig. 4. Similarly, when lever I l0 is moved into a position to cause the work shoe |,5 and grinding wheel to be moved into operative engagement with the work, the withdrawal of the T- shaped member |46 serves to allow the released tension of the springs |44 and |45 to automatically and simultaneously return the splash guard I4| to an operative vertical position, as indicated in Fig. 4.

For certain types of grinding, it may be desirable to provide an independent control for the vwork rest, to permit the work steadying shoe to be moved into operative eng-agement with the Work independent of the grinding wheel 20. A work rest control valve |50 is provided within the frame H1. This valve is preferably located in the pipe line |30 so that fluid under pressure may be admitted through pipe |30 to cylinder ||8 simultaneously with admission of fluid to move the grinding wheel 20. A plunger type valve |50 is provided having a control knob |5| i on the outer surface of the steadyrest. When it is desired to operate the steadyrest shoe ||5 independent of the wheel slide the operator pulls the knob |5| to move the valve |50 toward the left, as viewed in Fig. 3. This movement serves to prevent passage of uid through the pipe |30 to the cylinder 8. In this position of the valve, the operator may by manipulation of the lever ||0 cause the grinding wheel to move either toward or from the work Without causing a movement of the work rest.

In case it is desired to merely utilize the fluid pressure movement of the steadyrest shoe I5 as a/rapid positioning movement and to maintain the shoe in operative contact with the Work during grinding by manually rotating the adjusting Vknob |25, it is desirable that the splash guard |4| be moved into an operating position when the grinding wheel is brought into operative engagement with the work. In case it is desired to grind off rough spots on the work before the Work rest is brought into operative engagement with the work piece, lit is desirable that the work rest be moved into a position adjacent but out of contact with the rough piece of work and that bell crank lever the splash guard be moved into an operative position to prevent the splash of coolant iluid toward the front of the machine. The steadyrest mechanism and splash guardare arranged so that the shoe ||5 may be adjusted relative to the fluid pressure piston I I9 so that the shoe does not contact with the work when the piston is brought up against the end of the cylinder ||8.

In such a case, the splash guard and grinding wheel are moved simultaneously into an operative position for rough grinding the work. After the rough grinding operation 'has been completed and the rough spots ground off the periphery of thework piece, the manually adjustable knob |25 may then be rotatedto move the Work steadying shoe ||5 into operative contact with the Work piece.

In certain types of grinding, such as grinding rough crankpixivs, it is vdesirable Ato bring the grindingfwheel into engagement with the work to grind off the rough spqts on the work before the work rest is` brought into operative engagement therewith. vThe o `4erator first moves the control lever ||0 to cause the grinding wheel 20 to approach into operative engagement with the work. ,The operator, after the desired grinding has been accomplished, then pushes the control knob |5| toward 'the right,'as viewed in Fig. 3, to open to the valv |50 and admit iiuid under pressure through pipe |30 into the cylinder i8 to cause the shoe ||5 to be brought -into operative. engagement with` the surface o1' the work piece. In such an arrangement of the valves, the return movement of the steadyrest shoe is connected so that the steadyrest shoe ||5 and the grinding wheel 20 move simultaneously away from engagement with the work. Only the forward movement ofthe steadyrest shoe is controlled independent of the wheel slide.

An interlock may be provided between the work rest and the table traverse,'if desired, so that the table cannot betraversedwhen the work shoe isin engagement with the work. Such a mechanism may comprise an interlock which locks the table traverse control lever when the grinding wheel and work shoe are in engagement with the Work. A bell crank lever 60 is pivotally mounted on a stud |6| which is fixed to the steadyrest frame |I1. 'I'he short arm |62 of the bell crank lever |60 is provided with a. notch |63 which is arranged to engage a pin |64 (Fig. 4) on the table traverse control lever |03 so as to prevent movement of lever |03 When'the grinding wheel 20 and work rest shoe ||5 are in an operative position relative to the work. A spring (not shown) tends to normally hold the so that notch |63 engages pin |64 to prevent a traversing movement of the work supporting table.

l A pin |65 is mounted on-steadyrest slide l I6 and passes through an elongated slot |66 inthe short arm |62 into position |62a, thereby disen gaging notch |63 and unlocking pin |64 so as to allow movement of the table traverse control lever |03. Similarly, when the grinding wheel 20 and work shoe ||5 move into engagement with the work, the released tension of the spring serves to rock the lever |60 in a counterclockwise direction (Fig. 4) to lock the lever |03 and prevent a traversing movement of the work table.

The operation of this mechanism will be readily apparent from the foregoing disclosure. The operator iirst mounts a crankshaft to be ground in the work head, then by manipulation of the main control lever releases fluid under pressure to the cylinder 56, allowing the released tension of the springs in the clamping mechanism to clamp the `work rigidly 'in place. Movement of the control lever vinto a second position then serves to engage the clutch 38 to cause the work to rotate, and movement of control lever |03 serves to cause a longitudinal movement of the table l5 to bring the desired crankpin into operative engagement with the grinding wheel 20. In this position of the parts, the operator by manipulation of the control lever |0 may then cause agsimultaneous movement of the grinding wheel 20\ and the work steadying shoe ||5 into operativefengagement with the work, or a simultaneous withdrawal of the grinding wheel 20 and Work rest ||5, as desired. At the same time,lthe splash guard is automatically moved toward and from an operating position, so that when the steadyrest and the grinding wheel are moved to apoint remote from their operative position, the splash guard ||4 is rocked to an inoperative position, allowing the operator ready access to unload and load crankshafts in the machine Without the necessity of lifting' a heavy crankshaft up and over a high splash guard or avoiding the necessity o1' the operator having to lift v at each loading port to rotatably support a cylindrical work piece, v

a rotatable grinding wheel, a transversely movable Wheel slide 'supporting said wheel which is movable towards and from said work support to grind the work, a work steadying rest having a work engaging shoe which is movable into or out of engagement with the work to steady the same l during grinding, and a fluid pressure operated mechanism including a controlvalve to simultaneously move the wheel and shoe either towards or away from the work.

2. A grinding machine comprising a work support to rotatably support a cylindrical workpiece, a rotatable grinding wheel, a. transversely movable wheel slidesupporting said wheel, a fluid pressure operated mechanism to move said slide towards or from said work support, a work steadying rest having a work engaging shoe, a fluid vpressure operated mechanism to move said shoe into or out of engagement with the work to steady the same during grinding, and a iiuid pressure system including a control valve to simultaneously move the wheel and shoe either towards or from the work. v

3. In a cylindrical grinding machine, a longitudinally movablerotatable work support, a rotatable grinding wheel, a transversely movable wheel slide supporting said wheel, a iiuid pressure piston and cylinder operatively connected to move said slide, a work rest having a work steadying shoe, a fluid pressure piston and cylinder operatively connected to move said shoe into or out of engagement with said work, and a uid pressure system including a control valve arranged to admit uid under pressure simultaneously to each of said cylinders to cause the grinding wheel and shoe to move simultaneously towards the work to support and grind the same.

4. In a cylindrical grinding machine, a longitudinally movable rotatable work support, a rotatable grinding wheel, a transversely movable wheel slide supporting said wheel, a fluid pressure piston and cylinder operatively connected to move said slide, a work rest having a work steadying shoe, a fluid pressure piston and cylinder operatively connected to move said shoe into or out of engagement with said work, and a fluid pressure system including a control valve arranged to admit fluid under pressure simultaneously to each of said cylinders to cause the grinding wheel and shoe to move simultaneously away from engagement with the work after the grinding operation has been completed.

5. A grinding machine comprising a base, a longitudinally movable work support mounted thereon, rotatable work supporting members on said table, a wheel slide which rotatably supports a grinding wheel for transverse movement relative to said base, a work supporting shoe arranged to support and steady the work during grinding, a fluid pressure system including a piston and cylinder operatively connected to move said wheel slide transversely relative to the base either toward or from the work, a second fluid pressure piston and cylinder operatively connected to cause the shoe to approach or recede from engagement with the work, and means including a manually operable control valve to cause the grinding wheel and the work rest to simultaneously approach the work piece to support and grind the same and to simultaneously recede therefrom after a predetermined grinding operation has been completed.

6. In a cylindrical grinding machine, a longitudinally movable rotatable work support, a fluid pressure piston and cylinder operatively connected to move said support longitudinally of said machine, a rotatable grinding wheel, a transversely movable wheel slide supporting said wheel, a fluid pressure piston and cylinder operatively connected to move said slide toward or from the work, a work rest having a work steadying shoe arranged to steady and support the work piece, a fluid pressure piston and cylinder operatively connected to move said shoe into or'out of engagement with the work, a fluid pressure system including a control valve arranged to admit fluid under pressure ultaneously to the second and third cylinders t n ause a simultaneous movement of the grinding wheel and shoe either toward or from the work piece, and a main control valve arranged to prevent movement of the grinding wheel or shoe when the work table is being traversed.

7. A grinding machine having a base, a work support and a wheel slide which are slidably mounted thereon and arranged for a relative longitudinal and transverse movement relative thereto, a rotatable work support on the longitudinally movable member which is arranged to support a cylindrical work piece in operative relation with the grinding wheel, fluid pressure actuated system including a piston and cylinder artion and simultaneously withdrawn therefrom after the grinding operation has been completed.

8. A grinding machine comprising a base, a longitudinally movable work supporting table thereon, a rotatable work support on said table, a grinding Wheel slide carrying 'a rotatable grinding wheel mounted for transverse movement relative to the base to cause a transverse feeding movement of the grinding wheel, a fluid pressure system includinga piston and cylinder arranged to traverse the work support longitudinally relative to the base, a second fluid pressure piston and cylinder operatively connected to cause a transverse movement of the grinding wheel slide toward and from the work support, a work rest arranged to engage and support the periphery of the work, a fluid pressure piston and cylinder operatively connected to move said rest either toward or from the work, a. uid pressure system including interconnections between the wheel slide actuating cylinder and the work rest actuating cylinder, and a manually operable valve in said system arranged to simultaneously admit fluid under pressure to the wheel slide and the work rest cylinder to simultaneously cause the grinding wheel and the work rest to approach the work and/or to simultaneously recede from vengagement with the work after it has been ground to a predetermined size.

9. A grinding machine comprising a rotatable grinding wheel, a longitudinally movable rotatable work support, means including a control lever to traverse said support, a work rest havp interlock between said steadyrest shoe and traverse control lever which positively locks the control lever in a neutral position to prevent traverse of the work support when the shoe is in an operative position.

11. In a cylindrical grinding machine, a rotat- 'able grinding wheel, a rotatable work support, a

work rest having a work engaging shoe which is movable into and out of engagement with the work, means to move said shoe toward and from the work, a movable splash guard on the opposite side of the work support from the grinding wheel which is movable relative to said work support either to or from an operative position, andmeans to cause said work engaging shoe to move into operative engagement with the work and the guard to move simultaneously into an operative position before grinding is started and to simultaneously move to inoperative positions after the grinding operation has been completed.

12. A grinding machine comprising a transversely movable rotatable grinding wheel, a rotatable work support, a work rest having a work engaging shoe which is movable into and out of engagement with the work, means to move said shoe toward and from the work, a movable splash guard on the opposite sideof the work support from the grinding wheel which is movable to and from an operative position, and means to cause said grinding wheel and guard to move simultaneously into operative positions before the grinding operation and to move simultaneously to inoperative positions after the grinding operation has been completed.

13. In a cylindrical grinding machine, a rotatable grinding wheel, a rotatable Work support, i

a work steadying r'est having a work engaging shce which is movable into or out of engagement --with the work, a movable splash guard mounted on said rest, means to move said shoe into orout of operative engagement with the work, and means operable in timed relation with the shoe movement to move said guard into or out of operative position so as to enable the operator to unload a work piece being ground after the grinding operation has been completed without the -ne` cessity of reaching over a high splash guard.

14. In a cylindrical grinding machine, a transversely movable rotatable grinding wheel, a rotatable lwork support, a work steadying rest having awork engaging shoe which is movable into and out of engagement with the work, a movable splash guard on the opposite side of the work support from the grinding wheel which is arranged to be moved into or out of operative position, means to move said shoe towards and from the work, and means operable in timed relation with said work shoe movement to move the guard into an operative position when the shoe is moved into engagement with the work.

15. In a cylindrical grinding machine, a rotat-able grinding wheel, a rotatable work support,

a Work steadying rest having a Work engaging shoe which is movable into or out of engagement with the work, a movable splash guard which is arranged to be moved into or out of an operative position, means to move said shoe into or out of operative engagement with said work, yieldab'le means normally tending to hold said splash guard in an operative position, and means carried by said Work shoe to move said guard to an inoperative position when the Work shoe is moved away vfrom the work.

HERBERT A. SILVEN. 

